The Manufacturing Confectioner • January 2019 47
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Enzymes are nature’s catalysts for initi-
ating biochemical reactions. They are
present in all living organisms regulating var-
ious chemical reactions and all aspects of cell
metabolism, including the digestion of food.
Enzymes allow larger nutrient molecules to
be broken down into smaller molecules to
be metabolized. More than 5,000 reactions
catalyzed by enzymes have been identified.
The primary enzyme used in confec-
tionery production is invertase, which con-
verts sucrose into glucose and fructose. It
is necessary to soften or control crystalliza-
tion in product centers, and for other uses
as well. Herein is an overview of enzymes
including their chemistry and processing
conditions, and how to use invertase to gen-
erate desired results in confections. Other
enzymes used in confectionery applications,
and the methodology and benefit of their
uses, are outlined as well.
AN OVERVIEW OF ENZYMES
Enzymes are very large, three-dimensional
proteins, made up of several hundred amino
acids. On this large molecule, a specificregion exists where substrate molecules bindand undergo various chemical reactions.This region is known as the active site (Fig-ure 1). Essentially, the active site consistsof a section on the enzyme that form tem-porary bonds with a compound and in doingso, catalyze a reaction.A particular enzyme can only do its unique
work with a specific compound and onlyunder the right conditions. A lock and keyanalogy is often used to describe the speci-ficity of how any given enzyme, the lock,will react on a compound, the key. This reac-tion process is illustrated in Figure 2. In thisanalogy, only a correctly sized substrate keywill fit into the active site keyhole on theenzyme to unlock it. Once done, the subse-quent reaction steps can occur. In reality,the lock and key are based upon specificchemical bonds and structures.The nomenclature for enzymes is typi-
cally the compound that is being catalyzed,also known as the substrate, followed bysuffix ase, derived from a Greek word mean-
Working with Enzymes inConfectionsEnzymes play an essential role in making confections. Optimal conditions for their use are critical to ensure quality end product.
David JordanCenterchem, Inc.
David Jordan is thedirector, technical salesand services for Cen-terchem, Inc. His respon-sibilities include ingredi-ent sales and technicalsupport. He has beenwith the company for 16 years and previouslyheld positions at Her-shey Foods, Colorconand Enzyme Develop-ment Corp.
ing to separate. Examples of these includeamylases (amylose), proteases (proteins),lipases (lipids or fats) and cellulases (cel-lulose). There are exceptions to this cate-gorization. An enzyme can also have amore specific function, such as lactase,which breaks down lactose into galactoseand glucose; and saccharase, which cat-alyzes the hydrolysis of sucrose into glu-cose and fructose. The enzyme saccharaseis more commonly known as invertase inthe confections industry.Within a given category, there can be
different enzymes that will react with thespecific variations of the substrate. Forinstance α-amylase randomly hydrolyzesthe α-1-4 bonds on amylose, while glu-coamylase hydrolyzes α-1-4 and α-1-6bonds stepwise, starting from the non-reducing end. Similarly, different lipaseswill react and cleave different fatty acids,yielding unique flavor profiles. These dif-
fering reactions are the essence behind the
vast array of cheeses we enjoy.
In similar fashion, during the cocoa bean
fermentation process, naturally occurring
microorganisms release their unique set of
enzymes that generate various flavor com-
pounds of chocolate. For this discussion,
understanding that enzymes work in a very
specific manner is what is most important.
In these examples, the enzymes are clas-
sified as hydrolases because hydrolysis
occurs, resulting in a splitting of the com-
pound. However, not all reactions involve
splitting. Examples of other enzyme reactions
can be ligases, which combine molecules;
transferases, which transfer specific functional
groups from one molecule to another; and
isomerases, which rearrange atoms.
In the human body, our saliva contains
amylases, which help break down starches
as soon as they enter our mouth. Our
digestive tract, including liver, pancreas
and intestinal flora, all generate various
enzymes to aid in digestion. The lack of
these enzymes can manifest in various mal-
adies, primarily digestion issues, such as
gas and bloating.
There are many dietary supplements
based on the concept of ensuring there are
enough digestive enzymes in our systems.
There are also specific products such as lac-
tase for those who are lactose intolerant. A
common supplement, alpha-galacdosidase
aids in the digestion of certain typically indi-
gestible compounds (commonly found in
beans), which will ultimately sit in the gut
and “ferment” with the unpleasant side
effects we are undoubtedly familiar with.
ENZYME SOURCES AND PROPERTIES
Commercially, enzymes are derived from
three primary sources: plant, animal and
microbial (Figure 3). Those derived from
plants and animals have specific properties
Working with Enzymes in Confections
Within a givencategory, there can be
different enzymesthat will react with
the specific variationsof the substrate.
48 January 2019 • The Manufacturing Confectioner
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Figure 1
Enzyme Molecular Structure
Figure 2
Lock and Key Model of Enzyme Reaction
Amino Acid Chain
Active Site
while those from bacteria have a muchbroader range of applications. Enzymesalso have the ability to undergo variousgenetic modifications to help generate spe-cific functionality and properties. Whenenzymes are manufactured or purified,they typically go through a standardizationstep where they are diluted for a specificactivity. The activity is a measurement ofthe amount of active sites present, usuallystated per gram.Some microorganisms are used to pro-
duce a wide range of enzymes. For instance,the enzymes pectinase, cellulase, amylase,lipase and even invertase can all be com-mercially derived from the organismAspergillus niger. Based on the productionmethod used, there will be a main activityand then, lesser side activities. However, aselected strain of the yeast Saccharomyces
cerevisiae will produce an invertase withno side activity.Another unique property of enzymes is
that they are not consumed in a chemicalreaction. The enzyme finds a substrate toact upon and then moves on to the nextsubstrate. The enzyme remains active untilit runs out of substrate sources. Because ofthis property, the amount of enzyme addedis directly proportional to the time it takesto complete the reaction. If you have anenzyme with an activity of 10,000, it willtake one-tenth the amount of time to workas the same enzyme with an activity of 1,000.Every enzyme also has a unique set of
temperature and pH ranges at which theyare optimally effective. Outside of theseranges, the enzyme effectiveness decreases,ultimately becoming completely ineffec-tive. If enzymes are heated beyond a cer-tain point, they are denatured and irre-versibly deactivated as indicated in theFigure 4 graphs for invertase.When used in food processing, enzymes
do not need to be identified on a finishedproduct label if they are deactivated. Ifhowever, the product does not go throughthis denature step, the enzyme used in theprocess should be indicated.There are many types of enzymes used
in the food industry for the production ofa wide variety of products. Yeast is basicallya bundle of enzymes used in making bread,beer, wine and other fermented products.Yeast has many enzymes that break downthe different starches and sugars makingthem more easily fermentable. Fruit juiceproduction utilizes cellulases and pectinasesto optimize yield and clarify the juice. Andof course, there is invertase, the primaryenzyme and key ingredient used in the pro-duction of many confections.
USING INVERTASE IN CONFECTIONS
Invertase is an enzyme that converts thedisaccharide sucrose molecule into itsmonosaccharide components of glucoseand fructose (Figure 5) and as mentionedearlier, this conversion plays a critical rolein confection making. This process is called
Working with Enzymes in Confections
Another uniqueproperty of enzymesis that they are notconsumed in achemical reaction.
The Manufacturing Confectioner • January 2019 49
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The first chart shows solution at the optimal pH of 4.5; observe what happens whentemperature changes. Second chart shows solution at the optimal temperature; ob-serve what happens when pH changes.
Figure 4
Temperature and pH Impact on Invertase Activity
Figure 5
Invertase Hydrolyzes Sucrose into Glucose and Fructose
Figure 3
Sources of Enzymes
1. Fruit and Plant Sources • Papaya –Papain • Pineapple –Bromelain • Figs –Ficin
2. Animal Sources • Egg white –Lysozyme • Calf stomach –Rennet
3. Microbial Sources • Yeast (Saccharomyces) • Fungi (Aspergillus) • Bacteria (Bacillus)
inversion. Sucrose has limited solubility in
water at room temperature. Based on the
concentration, it will crystalize in a short
timeframe. Because glucose and fructose
have a greater solubility in water, they will
no longer crystallize after the sugar has
been inverted.
Commercially available invert syrup is
a high-solid content liquid that has gone
through this inversion process and is used
in food and beverage applications where
crystallization is undesirable. The tradi-
tional method of producing invert syrup
is to add acid to the concentrated solution.
Upon completion of the inversion process,
an alkali is added to raise the pH. This
process generates invert syrup that is eco-
nomical, but tends to have off colors and
flavors and cannot be considered organic.
Enzymatically-produced invert syrup
yields a much cleaner and a potentially
organic, product. Holding the syrup at an
elevated temperature, with a high enough
dosage of invertase so that the inversion
is complete in anywhere from 8 to 24
hours, produces a more purified end prod-
uct. Manufacturers must weigh the cost of
processing time and the energy used versus
cost of adding more invertase. As stated
previously, twice the invertase will enable
the reaction to take place in half the time.
Invertase is used in confections in two
primary ways (Figure 6). The most com-
mon application is to soften a product that
needs to start out firm. Examples of this
are a chocolate truffle or a chocolate-cov-
ered peppermint patty that is either
panned or enrobed. A hardened center is
made to withstand the panning process or
transport through an enrobing line. The
center needs to maintain its structural
integrity to enable it to be processed, pack-
aged and shipped. During warehousing or
en route to retailers, the invertase in the
product will begin to invert the sugar. As
the sucrose is inverted, becoming glucose
and fructose, the solubility increases and
the centers begin to soften. The finished
pieces are kept at a temperature that is
well below optimum and therefore, it takes
much longer for the inversion to complete
compared to invert syrup. This total time
can be easily adjusted by modifying the
dosage of invertase used.
The second way invertase is used in con-
fections is to control crystallization. An
example is a cordial cherry, a cherry in a
liquid surrounded by chocolate. Pieces are
often panned using a sugar solution that
contains invertase, but allowed to first crys-
talize so they can be chocolate panned.
Other cordial cherries made via depositing
are still in a viscous sugar fondant mixture
enabling the pieces to complete the enrob-
ing process. In both cases, the invertase
will liquefy the saturated sugar, allowing
Working with Enzymes in Confections
During warehousingor en route toretailers, the
invertase in theproduct will begin to
invert the sugar.
50 January 2019 • The Manufacturing Confectioner
➤Figure 6
Invertase Use in Confectionery
Softening center after panningor enrobing
Controlling crystallization for panningand extending shelf life
the finished cordial cherry to be sur-rounded by its requisite liquid syrup.Invertase can also prevent the product
from crystallizing over time, thus extendingshelf life. An example is a chocolate trufflemade via a one-shot depositor. The ganachecenter is fluid enough so it can be easilydeposited, however, this type of producthas a tendency to begin crystallizing as itsits. This causes the thin, fluid center tobecome harder and grittier, and therebyless desirable. The invertase will prevent,or at least significantly slow, this process.
Invertase Use Considerations
In the above applications, and in most con-fections where invertase is used, the productis never heated past the deactivation tem-perature of the invertase, which is typically190°F. Because the invertase is not deacti-vated, it must be identified on the final pack-age labeling.As previously mentioned, enzymes have
a specific temperature and pH range wherethey function optimally. Beyond that, theenzyme will be either less effective ortotally deactivated.These are important considerations when
determining the initial preparation andmanufacturing of a confection containinginvertase. Additional processing consider-ations when using invertase and enzymesin general, along with troubleshooting
points on issues that can arise, are outlined
in Figure 7. As an example, the center of a
chocolate truffle may require cooking or
heating. If the invertase is added too soon,
it could easily become deactivated resulting
in centers that remain hard. The invertase
must be added as the preparation cools
well below the deactivation temperature.
The order of invertase addition can also
be a factor. If an acid is being used, it is
important to add the invertase after the
acid has been thoroughly mixed. If not, the
invertase will come in contact with a highly
acidified area and thus become denatured.
Invertase can be derived from both a
fungal and a yeast source. These two
sources have slightly different pH and tem-
perature ranges and, in turn, have different
advantages. For instance, the optimal pH
of yeast-sourced invertase is 4.5 compared
to 3.0 for fungal-sourced. If a lower pH
product is being produced, the fungal-
sourced invertase type may be preferred.
Caution must be used with invertase from
a fungal source due to the possible pres-
ence of lipase, which could generate unde-
sirable side effects. If the confection con-
tains fat, lipase could cause the confection
to take on a soapy or cheese-like flavor
and an off odor.
This side effect can also occur if inclu-
sions or spices are used in the confections
that have not been properly processed.
Lipase can begin hydrolyzing the fat in the
piece and cause a soapy off-taste. This has
been noted in some starch-moulded gum-
mies and fruit snacks. If the starch is not
properly dried, residual moisture and bac-
teria in the starch will remain on the piece.
After the piece is oiled, the bacteria can
generate lipase, which will cause the oil to
yield an off taste.
Working with Enzymes in Confections
Invertase can bederived from both afungal and a yeastsource. These twosources have slightlydifferent pH andtemperature rangesand, in turn,advantages to oneversus the other.
The Manufacturing Confectioner • January 2019 51
➤Figure 7
Considerations and Troubleshooting
Processing Considerations• Order of addition• Cooking temperatures• Shelf life and transit time• pH of center• Labeling• Unwanted enzymes
Troubleshooting• Other ingredients processed with enzymes• Source of enzyme• Inclusions or spices• Improper starch cleaning
OTHER ENZYME CONSIDERATIONS
It is critical that there are no residualenzymes in any other ingredient in the con-fection. Amylase enzymes are used to processstarches and syrups. If any residual amylaseis present, it will cause hydrolysis of the starchin the confection. Similarly, if fruit juice isused in a pectin-based candy, any residualpectinase from the juice processing can inter-fere with the confection properly setting up.These cases are rare, but should be consid-ered if there are unexplained reactions takingplace within the piece.There are a few lesser-used applica-
tions for enzymes in the confectioneryindustry. Manufacturers of chocolatesauce have found that when the productsits in the container it can thicken, causingpumping to be harder, and the productto become less desirable. This effect isthe result of naturally occurring starch,pectin and cellulose —primarily from thecocoa pulp and shell fragments findingtheir way into the chocolate during theearly stages of the chocolate makingprocess. Thalia Hohenthal and MichelleWeinberg from Guittard Chocolate havea patent on the use of an “enzyme cock-tail” to help break down these com-pounds for improved flow capabilities.
Hohenthal, Thalia et al; June 30, 1998. HighCocoa/Chocolate Liquor Syrups withImproved Flow Properties; US patent5,773,056.
Using confections as a carrier for theenzymes as dietary supplements hasproven challenging. There is an added costto this step which to date has not been war-ranted, however technology is available toensure proper enzyme encapsulation.Another area of potential use for
enzymes within the confectionery industryis to help process scrap. As companiesstrive to decrease environmental footprints,
the ability to reclaim scrap is increasinglyimportant. Scrap can often be reused asfeedstock for subsequent batches, however,only in limited amounts. It is possible touse enzymes to break down sugars,starches, pectins or proteins (gelatin) thatare present in confectionery scrap prior tobeing used as feedstock.Other compounds considered waste
byproduct can be helped via enzymes. Forexample, the fruit juice industry treats filtermembranes with enzymes to help cleanthem, reducing the expense and manpowerassociated with frequent filter changes.Such operations should be evaluated on
whether the addition of enzymes is prac-tical in increased time and cost comparedto current methods of handling waste.However, with a basic understanding ofthe functionality of these compounds, find-ing other beneficial uses for enzymes islikely very possible and would make inter-esting studies.
CONCLUSION
In summary, enzymes are a natural way tohydrolyze various organic compounds.Invertase, by way of modifying the chem-istry and solubility of sucrose, is prevalentin many confections. The benefits to usinginvertase as well as other enzymes arequite significant, as long as necessary pre-cautions are taken and appropriate con-ditions are employed to optimize their use.The potential exists to use enzymes in
other aspects of confectionery processing,however, these areas need to be furtherexplored. Enzyme suppliers can provideall the information needed to optimize theuse of these important and essential con-fectionery ingredients. n
Working with Enzymes in Confections
The potential exists touse enzymes in other
aspects ofconfectionery
processing, however,these areas need tobe further explored.
52 January 2019 • The Manufacturing Confectioner
Presented at the AACT National Technical Conference